Cutting oil composition



Patented Oct.14, 1947 UNITED STATES PATENT OFFICE CUTTING OIL COMPOSITION York No Drawing. Application June 8, 1944, Serial No. 539,390

3 Claims. (Cl. 25248.6)

This invention relates to an improved cutting oil composition containing suliurized talloil and free from deposition of sludge.

U. S. Patent 2,198,562, Method of making sulfurized cutting oils, to Arthur Pollak and Randall Hastings, assignors to West Virginia Pulp & Paper Company, discloses that the use of sulfurized talloil, cut back with other oils such as mineral oils, presents some difliculty in that ordinarily the sulfurized oil deposits a sludge upon standing Which detracts from the usefulness of the oil for cutting purposes. A method is given wherein the resultant sludge deposition is kept at a minimum. This method consists in using a refined talloil and sulfurizing it at controlled conditions of time and temperature, namely from 2 to 4 hours, within a temperature range of 300 F.- 400 F. However a certain amount of sludge still separates from mineral oil blends, both paraffinic evaluation in the threading of a 2 inch seamless steel tubing showed that a large amount of sludge separated out overnight, the sticky mass adhering to the machine tool parts and being diflicult to remove.

The sulfurized talloil used in the above experiments was made from refined talloil and in accordance with the teachings of the Pollak- Hastings patent.

This invention is based upon the discovery that the addition of aromatic solvents to cutting oils containing sulfurized talloil prevents separation of sludge, and in extreme cases of slight separation, the sludge is of such a nature that it does not adhere to the metal surfaces. The aromatic solvents used in the experimental work were those derived from high temperature catalytic conversion of petroleum oils, specifically those derived from recycle stocks from catalytic crackand asphaltic, upon standing, as admitted in the 20 ing. Characteristics of solvents used are given patent specification. This deposit being quite below.

gummy and sticky adheres to the metal surfaces of the lathe, tools and pump parts, thus prevent- M d, H

ing their normal operation. 8

The above drawbacks have been confirmed in 25 s i it s ti iit experiments. When a. blend of 6% of sulfurized refined talloil (Indusoil) and 94% of pale parafiin Grav. APL' 12 3 oil was installed in a test lathe for purposes of 55 gg gg i evaluation of the sulfurized base, after standing Ani i e Pt..f{ I:

in the machine tool over the week end, the coolant Appmx 301mg R F 500'600 600-760 pump was so badly gummed up that it was necessary to disassemble it for cleaning. The ways of t lathe were coated with a Sticky film which blends listed, the sulfurized talloil was made by prevented the passage of the carriage. A similar sulfurizing Indusoil- (refined talloil) to a 15% blend, installed in pipe threading machine for sulfur content at a temperature of about 350 F.

Table I Experimental data are tabulated below. In all Stability of Blend Blend After Standing 1 week After Standing 5 weeks 91% 100" paraflin oil--- 3% Suliurized 'lalloi1 5% Med. Aro. Solvent 92% 100 paraflin oil.-- 3% Sulfurized TalloiL. 10% Med. Aro. Solven do Appreeiable separation.

}Cloudy, slight separation Slight separation (deposit not adhesive).

87% 100 paraflin oili.

}Clcar, trace of separation Clear, trace of separation (material which separated out not adhesive.

Readily dispersed). }Clear, no separation Clear, trace of separation (material which separated out not adhesive. Readily dispersed). g% l? l }Cloudy, much separation Clear, large amount of separated material. 3 n urize a oi Qoastal (Awhaltic) OiL }C1oudy, considerable separation. Cloudy, considerable separation. 82 3 1 36}?gfiggflkk m o }Slight separation Slight separation, Sticky deposit. 6% Sulfurized TalloiL 15% Med. Aro. Solven Clear, no separation Trace of separation-material separated out not adhesive, readily dis- 79% Coastal Oil. persed.

It will be seen from the above data that the incorporation of or more of the aromatic solvent produced cutting oils satisfactory from the standpoint of stability and freedom of sludge deposition, whereas blends of sulfurized talloil with either paraflinio or asphaltic oils invariably failed in that respect. Even in cases when some separation was observed with smaller additions Percent Sulfur-ized refined talloil sulfur) 6 Hy..Aro. solvent 15 100" paraffin oil 79 The above product was evaluated in the threading of 2 inch seamless'steel tubing'and left in the machine over night. No sticky resinous deposit was observed on parts of the machine toolor on the work. The oil was drained from the machine into an iron pail-and allowed to stand for several days. No instability of the oil was indicated.

The metal cutting efficiency of theabove blend was compared with that of a conventional sulfurized fat base cutting'oil. The latter contained the same 'percentof sulfur, in the base and in the finished cutting oil. The threading efiiciency oi the two products under comparison, as expressed in kilowatts or specific power consumption was the same. This indicates that the performance of the "stabilized sulfurized talloil blend compared favorably with blends of conventional sulfurized fat bases,

The aromatic oils used for this stabilizationiare in general derived from the high boiling portions of a material which has been subjected to severe cracking and find no counterpart in uncracked oils of similar boiling :point. The :nature of the oils to be used may be noted'from the'fo'llowing table :of properties defining oils useful for the Most striking of these properties is the combination of viscosity and gravity, wherein the It i believed that combination of .low viscosities, (BO-200' S. U. V. F.), with high gravities (.9'7-1.06), (as

heavy as water, practically), indicates an oil of a nature quite difierent from those found in ordinary lubricants, either distillate or residual.

'I'hese oils should be incorporated into the final composition to the extent of from 5% to 30% of the final composition, the preferable range being from 10% to 20%, and the apparent optimum being about 15%.

1. A sulfurized talloil cutting oil composition stable against the formation of sludge comprising a mineral oil lubricating fraction, a sulfurized talloil, and. irom about 5% to about 30% of a hydrocarbon oil having an aniline point of +40 F. or lower, a specific gravity of from 0.9 to 1.06, a flash point of 250F. minimum, an initial boiling point of not less than 450 F., and a viscosity of not over about 200 seconds Saybolt Universal at 100F.

2. A .sulfurized talloil cutting oil composition stable against theformation of sludge comprising a mineral oil lubricating fraction, a sulfurized talloil, and from about 10% to about 20% of a hydrocarbon oil having an aniline point of +40 F.-.or.-1ow-er, aspecific gravity of from 0.9 to 1.06, aflash point :of 250 F. minimum, an .initial boiling .=pcintofnot less than 450 F., and a viscosity of notover about 200 seconds Saybolt Universal at 100F.

3.. A sulfurized talloil cutting oil composition stableagainst the .formation of sludge comprising a mineral oil lubricating fraction, a sulfurized talloil and-about 15% of a hydrocarbon oil having an aniline point of +40 F. or lower, a specific gravity of.from'0.9 to 1.0.6,:a fia-shipoint of .250 F. minimum, an initial boiling pointof notlessthan 450 and a viscosity of not over about 200 seconds Saybolt Universal at 100 .F.

LOUIS H, SUDHOLZ.

CECIL D. 'FLEMMING.

REFERENCES CITED Thetfnllowing references are of record in the file .of this patent:

UNITED STATES PATENTS OTHER REFERENCES American Mineral Spirits Co. publication (US. Patent Office Library) Jan. 9, 1943. 

